Loop and lock stitch sewing-machine



(ModeL) 2Sheets--Sheet 2.

- J. W. BLODGETT.

LOOP AND LOCK. STITCH SEWING MACHINE.

No. 250,705. Patented Dec. 13,1881.

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FFIGEQ JOHN W. BLODGETT, OF CHICAGO, ILLINOIS.

LOOP AND LOCK STITCH SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 250,705, dated December13, 1881.,

Application filed March 19, 1880.

To all whom it may concern Be it known that I, JOHN W. BLODGETT,residing at Chicago, in the county of Cook and State of Illinois, and acitizen of the United States, have invented new and useful Improvementsin Sewing-Machines for Forming Oombined Loop and Lock Stitches, of whichthe following is a full description, reference being had to theaccompanying drawings, in which- Figure 1 is a side elevation of asewing-machine having my improvements applied thereto; Fig. 2, an endelevation of the same; Fig. 3, a detail showing the arm which carriesthe roller or stud for imparting a curvilinear movement to the loop-arm;Fig. at, a detail showing the devices for giving the curved backwardmovement to the hook-arm; Figs. 5, 6, 7 8, and 9, details showing thevarious positions of the loop-arm while the loop is being made.

This invention is primarily designed for use in completing the upper orouter face of a button-hole, but may be used for other purposes, and hasfor its object the forming or making of a combined loop and lock stitchby automatic means, so as to produce an overstitched button-hole-havin ga more finished appearance, and resembling what is termed a hand-madebutton-hole and my invention consists in providing a pin or stud locatedon the needlebar, and arranged to engage wit-h a cam-slot in theloop-hook and give the lower or hook end of such hook a reciprocatingmovement, combined with a bar or support carrying a stud or roller whichengages with a curved face and projection on the loop-hook and gives thelower or hook end thereof a curvilinear movement.

In the drawings, A represents the loop-hook, formed from a single piece,with its lower end bent so as to stand in the direction of the needleswhen ready for use, and form the threadcatcher. The upper end of thisloop-hook A extends up, as shown, into a recess, vb, cut or formed inthe lower end of the head of the machine, and is supported by a pin, a,in such manner as to allow it to swing therefrom, and its upper end toslide back and forth thereon between the walls of the recess. Around thepin a, and between the end of the loop-hook A and the wall of the recessb, is a coil-sprin g, c, which acts against the upper end of the loop-(Model) book A. The lower or curved-in end (1 of the loop-hook A has anotch, 0, cut therein to catch the thread, which notch should be ofsufficient depth to receive the thread and retain it while being looped.The main portion of the hook A has a slot, f, one portion of which isstraight and the other portion curved or otherwise formed, so that asthe pin 9 moves therein it will give a reciprocating movement to thelower end or thread-catcher d of the hook. The pin g, as shown, isfirmly secured in the front side of the needle-clamp, and projectsthrough the slot f, with its sides in contact with the sides of theslot, so that as the needle-bar is operated the pin will actuate theloop-hook.

B is a rigid bar, the upper end of which is firmly secured to the headof the machine. This bar projects down, and its lower end is bent atright angles to the main portion, and at its end is provided with acircular stud or roller, h, which roller or stud enters a curved grooveor slot formed for it in an arm or side extension, 7c, of the loop-hook,in any suitable manner, (see Fig. 4,) so that as the loop-hook isreciprocated its lower end will have a curvilinear movement backward inthe are of a circle given to it by the action of this curved face j andthe stud or roller h. On the arm or extension k is a projection, i,which strikes the stud or roller h and throws the lower end of theloop-hook back away from the needles, so as to prevent the thread frombeing caught around the needle as it is looped around.

0 is the needle-clamp; D, the needle-bar, and E the head of an ordinarysewing-machine. These parts may be of any of the well-known and usualforms of construction for such parts. In the form of construction andarrangement shown the thread of the right-hand or inner needle is caughtby the notch e and carried or looped around the other needle.

The operation is as follows: When the neeble-bar is at its highest pointof ascent the pin 9 is in the curve at the upper end of the curvedportion of the slot f, and the roller or stud h is in the outerextremity of its curved slot and to the left or outside of the stud orprojection i, in which position the loop-hook d. is carried beyond andback of the inner or right-hand needle, with the notch c in position tocatch the thread of such needle. As the needle-bar descends the pin 9,as it passes down the curve at the upper end of the curved portion ofthe slot f, will act to throw the loop-hook d to the left, whichmovement also causes the projection 1' to simultaneously strike the studor roller h, pass over it, withdrawing the point (I from the needlesmomentarily, and allowing the stud or roller to enter the innerextremity of its curved slot to the right of the projection, the rollerIt being in contact with the curved face j during such movement, so thatas the pin g reaches the end of theuppercurve of the curved portion ofthe slot f the point d will be thrown to the left and back of theleft-hand needle by the action of the pin g, and the roller or stud hcarrying the thread of the right-hand needle caught by the notch 0around the left-hand needle in the form of a loop, which movements takeplace before the needles have descended far enough to enter thematerial. Then as the needle-bar descends still farther the pin 9 willbe in contact with the face of the curved portion of the groove fbetween the curves, and the parts will remain in the position justdescribed. Then the pin gen ters thelower curve of the curved portionofthe slotf, which throws the hook d backward or to the right, so as toallow the thread caught by the notch e to slip therefrom, and at thesame time the projection i strikes the roller h and passes to the leftthereof, withdrawing the point at and swinging it around in front of theneedles, forming a lock and loop stitch. The needles finish their strokeduring the passage of the pin g down the straight portion of the slotf,during which operation the hook 01 remains stationary. Then the needlesascend, and the pin gpasses up in the straight portion of the slot f,thepointcl still remaining stationary, while the pin gpasses up in thispart of the slot f,infront of theneedles. Then as the pin 9 enters andpasses through the lower curve of the curved portion of the slotf thepoint 61 will be thrown to the left and forward by the action of the pin9 and roller h,

and will remain in that position while the pin 9 passes through theportion between the upper and lower curves of the curved portion of theslot. Then as the pin 9 enters and passes to the extremity of the uppercurve of the curved portion of the slot f the point (Z will be thrownaround in the arc of a circle to and back of the right-hand needle, bythe action of the pin 9 and roller h, to the proper position for againcatching the thread of the right-hand needle, and by the descent of theneedle bar looping it around the left-hand needle, which movements willcontinue until the machine is stopped. By reversing the direction of thecurves of the slot f and locating the notch e on the opposite side ofthe point d the action of the loop-hook will be reversed, and thelefthand thread be caught and looped around the right-hand needle.

Tension and take-up devices for the thread are shown in Fig. l of thedrawings; but as they form no part of this invention, and are made thesubject-matter of a separate application of even date herewith, they arenot here specifically described.

What I claim as new, and desire to secure by Letters Patent, is

1. The loop-hook A, having a projection or cam, i, and a curved groov'eor face, 3', in combination with the bar or support B, having a stud orroller, h, to engage with cam iand groove j for giving the loop-hook amovement in the arc of a circle, substantially as and for the purposesspecified.

2. The loop-hook A, having a slot-,f, and a cam, t, and curved groove orfacej, in combination with the needle-bar having the pin or stud g, andbar or support 13, carrying the circular stud or roller h, substantiallyas and for the purposes specified.

- JOHN W. BLODGETT.

Witnesses:

O. W. BOND, B. A. PRICE.

